The present invention generally relates to anti-siphon fuel filler systems. More particularly, the invention relates to an anti-siphon fuel filler assembly having restriction means for preventing unauthorized fuel removal and means for preventing the premature deactivation of automatic fuel dispensing systems caused by reverse fuel flow.
The increasing cost of petroleum products has created a corresponding increase in fuel theft. Fuel theft is especially widespread in the trucking industry. To remove fuel from a truck or other vehicle, a siphon hose is commonly inserted through the filler neck tube into the fuel tank. The application of suction through the hose permits the withdrawal of fuel.
Various devices have been created which prevent access to the interior of the fuel tank. Many such devices use lock mechanisms. However, these devices are easily opened and generally ineffective. Furthermore, most require the use of a key. Loss of the key presents significant problems, especially if the vehicle operator has a delivery or travel deadline. Also, lock mechanisms frequently malfunction during cold and inclement weather. A need therefore exists for an improved anti-siphon system which prevents fuel theft in a simple and efficient manner, while avoiding the use of keys or lock mechanisms.